I hate it when I make stupid errors. If I didn't know the answer, then I'm fine with it. However, I become mad when I make a stupid error. For example, I was finding the stability of a system by using a Routh Array and I transcribed the wrong numbers when I went to solve for K. So dumb. Why couldn't I have just wrote the same numbers? But no, I had to write different numbers for no reason. AARRRGGHHH!!!